Anti-inflammatory activity of Maytenus senegalensis root extracts and of maytenoic acid

Maytenus senegalensis (Lam.) Excell (Celastraceae) root extracts were investigated for their topical anti-inflammatory properties by measuring the inhibition of the Croton oil-induced ear oedema in mice. The highest anti-inflammatory activity was detected in the chloroform extract, which reduced the oedematous response with a potency similar to that of the NSAID reference drug indomethacin (ID(50)=84 and 93 microg/cm(2), respectively). Fractionation of the chloroform and of the hexane extracts led to the isolation of maytenoic acid (1), which exhibited a dose-dependent antiphlogistic effect (ID(50)=0.11 micromol/cm(2)) twice that of indomethacin (ID(50)=0.26 micromol/cm(2)) and only three times lower than that of hydrocortisone (ID(50)=0.04 micromol/cm(2)).     

Coumarins from unripe fruits of Poncirus trifoliata

Petrol extracts of unripe fruits of Poncirus trifoliata L. were found to contain 7-geranyloxycoumarin, bergapten, imperatorin, 6-methoxy-7-geranyloxycoumarin and two new coumarins which were shown by chemical and spectroscopic means to be 7-(3′-methyl-2′,3′-epoxybutyloxy)-8-(3″-methyl-2″,3″-epoxybutyl)coumarin and 7-(3′-methyl-2′,3′-epoxybutyloxy)-8-(3″-methyl-2″-oxobutyl)coumarin respectively.     

O2-acetoxymethyl-protected diazeniumdiolate-based NSAIDs (NONO-NSAIDs): synthesis, nitric oxide release, and biological evaluation studies

A novel group of O2-acetoxymethyl-protected diazeniumdiolate-based non-steroidal anti-inflammatory prodrugs (NONO-NSAIDs) were synthesized by esterifying the carboxylate group of aspirin, ibuprofen, or indomethacin with O2-acetoxymethyl 1-[N-(2-hydroxyethyl)-N-methylamino]diazeniumdiolate. The resulting nitric oxide (*NO)-releasing prodrugs (7-9) did not exhibit in vitro cyclooxygenase (COX) inhibitory activity against the COX-1 and COX-2 isozymes (IC50s>100 microM). In contrast, prodrugs 7 and 8 significantly decreased carrageenan-induced rat paw edema showing enhanced in vivo anti-inflammatory activities (ID50's=552 and 174 micromol/kg, respectively) relative to those of the parent NSAIDs aspirin (ID50=714 micromol/kg) and ibuprofen (ID50=326 micromol/kg). The rate of porcine liver esterase-mediated *NO release from prodrugs 7-9 (2 mol of *NO/mol of test compound in 0.6-6.5 min) was substantially higher compared to that observed without enzymatic catalysis (about 1 mol of *NO/mol of test compound in 40-48 h). These incubation studies suggest that both *NO and the parent NSAID would be released upon in vivo activation (hydrolysis) by esterases. Data acquired in an in vivo ulcer index (UI) assay showed that NONO-aspirin (UI=0.8), NONO-indomethacin (UI=1.3), and particularly NONO-ibuprofen (UI=0) were significantly less ulcerogenic compared to the parent drugs aspirin (UI=57), ibuprofen (UI=46) or indomethacin (UI=34) at equimolar doses. The release of aspirin and *NO from the NONO-aspirin (7) prodrug constitutes a potentially beneficial property for the prophylactic prevention of thrombus formation and adverse cardiovascular events such as stroke and myocardial infarction.     

Synthesis and analgesic/anti-inflammatory evaluation of fused heterocyclic ring systems incorporating phenylsulfonyl moiety

A series of pyrazolo[1,5-a]pyrimidine, triazolo[1,5-a]pyrimidine, and pyrimido[1,2-a]benzimidazole ring systems incorporating phenylsulfonyl moiety were synthesized via the reaction of 3-(N,N-dimethylamino)-1-aryl-2-(phenylsulfonyl)prop-2-en-1-one derivatives 2a,b with appropriate nitrogen nucleophiles. The analgesic and anti-inflammatory activities of the newly synthesized compound were investigated in vivo. 3-Bromo-2-phenyl-6-(phenylsulfonyl)-7-(4-methylphenyl)pyrazolo[1,5-a]pyrimidine (5e) was found to have an excellent analgesic activity in comparison with indomethacin as a reference drug, while the highest anti-inflammatory effect was observed in the case of 2-(4-bromophenyl)-6-(phenylsulfonyl)-5-(4-methylphenyl)pyrazolo[1,5-a]pyrimidine (5d). From the structure-activity relationship (SAR) point of view, the analgesic/anti-inflammatory activity of pyrazolo[1,5-a]pyrimidine derivatives was found to be much higher than triazolo[1,5-a]pyrimidine and pyrimido[1,2-a]benzimidazole derivatives.     

Topical anti-inflammatory activity of flavonoids and a new xanthone from Santolina insularis

Bioactivity-guided fractionation of the methanol extract from the leaves of Santolina insularis led to the isolation of one new xanthone, (E)-3-(6-[(E)-3-hydroxy-3-oxo-1-propenyl]-9-oxo-9H-xanthen-2-yl)-2-propenoic acid, together with six known flavonoids: hispidulin, nepetin, cirsimaritin, rhamnocitrin, luteolin and luteolin 7-O-beta-D-glucopyranoside. The structures were elucidated by means of 1D-, 2D-NMR spectroscopy and mass spectrometry. The topical anti-inflammatory activity of all isolated compounds and extracts was investigated employing the croton oil-induced dermatitis in mouse ear. The most active compound, luteolin, showed an ID50 of 0.3 micromol/cm(2) and prevented ear oedema more effectively than an equimolar dose of indomethacin within 24 h.     

Synthesis, anti-inflammatory and analgesic activities evaluation of some mono, bi and tricyclic pyrimidine derivatives

3-Aminobenzonitrile and 2-amino-4-phenyl thiazole on condensation with 4-isothiocyanato-4-methyl pentane-2-one gave condensed monocyclic pyrimidine derivatives 1 and 2, 3, respectively. Condensation of 3-aminopropyl imidazole with 3-isothiocyantobutanal gave condensed monocyclic pyrimidine derivative 4. Bicyclic pyrimidine derivatives 5a and 5b have been synthesized by the condensation of diaminomaleonitrile with 4-isothiocyanto-4-methylpentane-2-one and 3-isothiocyanatobutanal, respectively. Condensation of 4-isothiocyanato-4-methyl pentane-2-one with 2,3-diaminopropionic acid hydrochloride yielded another bicyclic compound 7. 4-Isothiocyanato-4-methyl pentane-2-one, 3-isothiocyanatobutanal and 4-isothiocyanatobutan-2-one on condensation with 2-amino-4-nitro phenol gave tricyclic pyrimidine derivatives 8a, 8b and 8c, respectively. Structures of all the synthesized pyrimidine derivatives are supported by correct IR, 1H NMR and mass spectral data. The anti-inflammatory activity evaluation was carried out using carrageenin-induced paw oedema assay, and compounds 1, 3 and 5b exhibited good anti-inflammatory activity, that is, 27.9, 34.5 and 34.3% at 50 mg/kg po, respectively. Analgesic activity evaluation was carried out using phenylquinone writhing assay and compounds 5a, 5b and 8b showed good analgesic activity, that is, 50, 70 and 50% at 50 mg/kg po, respectively.     

Photocleavage of o-nitrobenzyl ether derivatives for rapid biomedical release applications

The externally controlled cleavage of covalently linked prodrugs, proteins, or solid-phase formulation vehicles offers potential advantages for controlled drug or gene delivery. A series of o-nitrobenzyl ester compounds (1-8) were synthesized to allow a systematic study of photolability. The o-nitrobenzyl ester was strictly required for photolability, while imido esters were not photolabile. The degradation kinetics of 1-o-phenylethyl ester was an order of magnitude faster than that of o-nitrobenzyl ester. Tosylate, phosphate, and benzoate derivatives of 1-o-nitrophenylethyl displayed similar photolability (>80% decomposition within 10 min at 3.5 mW/cm2 at 365 nm). O-o-Nitrobenzyl O',O'-diethyl phosphate displayed the fastest decomposition at photoirradiation condition (3.5 mW/cm2, 365 nm) suitable for biological systems. We report the synthesis and photo-decomposition of 1-o-nitrophenylethyl derivatives amenable for the creation of photolabile prodrugs or formulation particles for drug depots, DNA condensation, or tissue engineering applications.     

Synthesis, characterization and preliminary screening of regioisomeric 1-(3-pyridazinyl)-3-arylpyrazole and 1-(3-pyridazinyl)-5-arylpyrazole derivatives towards cyclooxygenase inhibition

In a search for novel compounds with analgesic and anti-inflammatory activity, a series of regioisomeric 1-(3-pyridazinyl)-3-arylpyrazole (5a-f, 6a-f) and 1-(3-pyridazinyl)-5-arylpyrazole (7a-f, 8a-f) derivatives were synthesized. The structure of these regioisomers was confirmed by spectral techniques. The compounds were preliminarily screened at 8 microM concentration for their inhibitory activity against cyclooxygenase enzymes, COX-1 and COX-2, using a human whole blood test. The tested derivatives showed inhibitory activity for both enzymes and are worthy of further investigation for developing better leads.     

Toxicity and inhibition of feeding and tunneling response of naphthalene and 10 derivatives on the formosan subterranean termite (Isoptera: Rhinotermitidae)

In laboratory choice tests with either filter paper treatment or sand treatment, naphthalene and 10 derivatives were evaluated for their effects on the behavior of the Formosan subterranean termite, Coptotermes formosanus Shiraki (Isoptera: Rhinotermitidae). After 24-h exposure, workers avoided 50-microg/cm2-treated filter paper with 1'- and 2'-acetonaphthone. By day 8, feeding activity on filter paper treated with 1- and 2-methoxynaphthalene, 1'- and 2'-acetonaphthone were significantly reduced compared with the controls. Naphthalene and six other derivatives were not effective at 50-microg/cm2-treated filter paper. After 12-d exposure, tunnels constructed in sand treated with 1- and 2-methoxynaphthalene (0-3 cm2), 1'- and 2'-acetonaphthone (2-9 cm2), 2-naphthalene methanol (14-19 cm2), or 2-isopropylnaphthalene (16-19 cm2) at the rate of 100 mg/kg sand were significantly less than the controls (34 cm2). Consumption on filter paper placed on sand treated with 1- and 2-methoxynaphthalene and 1'- and 2'-acetonaphthone was significantly reduced (0-7 mg) compared with the controls (33-54 mg). 1-Methoxynaphthalene was the only treatment that caused significantly less feeding activity in the untreated sand chamber (0-6 mg) compared with the control (63-128 mg).     

Design,synthesis, anti-inflammatory activity,and molecular docking studies of perimidine derivatives containing triazole

We report here the design, synthesis, and anti-inflammatory activities of a series of perimidine derivatives containing triazole (5a–s). The chemical structures of the synthesized compounds have been assigned on the basis of IR, ¹H NMR, ¹³C NMR, and HRMS spectral analyses. The anti-inflammatory properties of the synthesized perimidine derivatives were evaluated in a lipopolysaccharide (LPS)-stimulated inflammation model. Among the tested compounds, compound 7-(3-methylbenzyl)-7H-[1,2,4]triazolo[4,3-a]perimidine (hereafter referred to as 5h) and compound 7-(2-fluorobenzyl)-7H-[1,2,4]triazolo[4,3-a]perimidine (hereafter referred to as 5n) caused a reduction in the levels of the pro-inflammatory cytokines—tumor necrosis factor (TNF)-α and interleukin (IL)-6—in RAW264.7 cells. The anti-inflammatory potential of compounds 5h and 5n was also evaluated in vivo in a xylene-induced ear inflammation model. Compound 5n showed the most potent anti-inflammatory activity with an inhibition of 49.26% at a dose of 50 mg/kg. This activity is more potent than that of the reference drug ibuprofen (28.13%), and slightly less than that of indometacin (49.36%). To further elucidate the mechanisms underlying these inhibitory effects, LPS-induced nuclear factor-κB (NF-κB) activation and mitogen-activated protein kinase (MAPK) phosphorylation were studied. The results of western blotting showed that the extract obtained from compound 5n inhibited NF-κB (p65) activation and MAPK (extracellular signal-regulated kinase (ERK) and p38) phosphorylation in a dose-dependent manner. Moreover, the results of a docking study of compound 5n into the COX-2 binding site revealed that its mechanism was possibly similar to that of naproxen, a COX-2 inhibitor. The effect of compound 5n on COX-2 antibody was showed it could significantly inhibit COX-2 activity.     

Evaluation of novel microtubules interfering agents myoseverin, tubulyzine and E2GG in primary cultures of rat hepatocytes

We investigated the effects of novel microtubules interfering agents (MIAs) in primary cultures of rat hepatocytes. Cells were treated for 24 h with a known compound colchicine and newly synthesized derivatives myoseverin, tubulyzine, and E2GG. We examined the effects of MIAs on microtubules network integrity and on the polymerization capability of isolated tubulin. All tested MIAs inhibited microtubules assembly with the following IC(50) values: tubulyzine (4.4 + or - 0.9 micromol/l), myoseverin (7.0 + or - 0.8 micromol/l), E2GG (16 + or - 2 micromol/l), colchicine (2.0 + or - 0.4 micromol/l). The potency of MIAs to perturb microtubular network integrity (monitored by immune-histochemistry) increased in the order tubulyzine < myoseverin < E2GG < colchicine. We described recently deleterious effects of MIAs on the expression of drug metabolizing enzymes, including CYP1A1. Here we observed inhibitory effects of novel MIAs on dioxin-inducible expression of CYP1A1 mRNA in rat hepatocytes. We conclude that novel MIAs exert analogical biological response as classical MIAs such as colchicine or nocodazole. This further supports the hypothesis that tubulin is the primordial target of MIAs within the cell and that perturbation of microtubules dynamics and/or integrity triggers the biological effects described here.     

Photosensitizers related to purpurin-18-N-alkylimides: a comparative in vivo tumoricidal ability of ester versus amide functionalities

For a comparative study, 3-(alkyloxyethyl)-3-devinylpurpurin-18-N-hexylimides with ester and amide functionalities were investigated for tumor selectivity and in vivo photosensitizing efficacy. Compared to amide analogues, the related photosensitizers with ester functionalities were found to be more effective. Among these compounds the 3-devinyl-(3-hexyloxyethyl)-purpurin-18-N-hexylimide as methyl ester 12 showed excellent tumor uptake (tumor versus muscle ratio: 8:1), and produced 100% tumor cure on day 30 at a dose of 1.0 micromol/kg. The mice were treated with light (135 J/cm2, 705 nm) at 24 h post injection of the drug.     

Synthesis, anti-inflammatory, analgesic and kinase (CDK-1, CDK-5 and GSK-3) inhibition activity evaluation of benzimidazole/benzoxazole derivatives and some Schiff's bases

A series of N-(acridin-9-yl)-4-(benzo[d]imidazol/oxazol-2-yl) benzamides has been synthesized by the condensation of 9-aminoacridine derivatives with benzimidazole or benzoxazole derivatives. Condensation of 2-hydroxy naphthaldehyde with functionalized diamines leads to the formation of Schiff's bases and not imidazole derivatives. All these compounds were characterized by correct FT-IR, (1)H NMR, MS and elemental analyses. These compounds were screened for anti-inflammatory, analgesic and kinase (CDK-1, CDK-5 and GSK-3) inhibition activities. Compounds 11 and 7e(f) showed good anti-inflammatory (35.8% at 50 mg/kg po) activity and good analgesic activity (60% at 50 mg/kg po), respectively. Compound 3b showed significant in vitro activity against CDK-5 (IC(50)=4.6 microM) and CDK-1(IC(50)=7.4 microM) and compound 3a showed moderate CDK-5 inhibitory activity (IC(50)=7.5 microM). The other compounds showed moderate anti-inflammatory and analgesic activities.     

白藜芦醇抑制大鼠海马 CA1区神经元放电

应用细胞外记录单位放电技术,在大鼠海马脑片上观察了白藜芦醇(resveratrol)对海马CAI区神经元放电的影响。实验结果如下：(1)在52个CAI区神经元放电单位给予白藜芦醇(0．05、0．5、5μmol／L)2min,有46个放电单位(88.5％)放电频率明显降低,且呈剂量依赖性;(2)预先用0．2mmol／L的L-glutamate灌流海码腑片,8个放电单位放电频率明显增加,表现为癫痫样放电,在此基础上灌流白藜芦醇(5μmol／L)2min,其癫痫样放电被抑制;(3)预先用L型钙通道开放剂Bay K8644灌流7个海马5脑片,有6个单位(85.7％)放电增加,在此基础上灌流白藜芦醇(5μmol／L)2min,其放电被抑制;(4)9个放电单位灌流一氧化氮合酶抑制剂L-NAME(N^0-nitro-L-arginine methylester)50μmol／L,有7个单位(77．8％)放电明显增加,在此基础上灌流白藜芦醇(5μmol／L)2min,放电被抑制;(5)10个放电单位灌流人电导钙激活性钾通道阻断剂TEA(tetraethylarnmonium chloride)1mmol/L后,有9个单位(90％)放电增加,在此基础上灌流白藜芦醇(5μmol／L)2min,8个放电单位(88,9％)放电频率明显减低。以上结果提示：白藜芦醇能抑制海马神经元自发放电以及由L-glutamate、L-NAME、Bay K8644和TEA诱发的放电,可能与白藜芦醇抑制L型钙通道,减少钙内流有关;似乎与大电导钙激活性钾通道无关。     

Diazen-1-ium-1,2-diolated nitric oxide donor ester prodrugs of 5-(4-hydroxymethylphenyl)-1-(4-aminosulfonylphenyl)-3-trifluoromethyl-1H-pyrazole and its methanesulfonyl analog: synthesis, biological evaluation and nitric oxide release studies

A new class of hybrid nitric oxide-releasing anti-inflammatory (AI) ester prodrugs (NONO-coxibs 12a-b) wherein an O(2)-acetoxymethyl 1-(2-carboxypyrrolidin-1-yl)diazen-1-ium-1,2-diolate (11, O(2)-acetoxymethyl PROLI/NO) NO-donor moiety was covalently coupled to the bromomethyl group of 5-(4-bromomethylphenyl)-1-(4-aminosulfonylphenyl)-3-trifluoromethyl-1H-pyrazole (9a), and its methanesulfonyl analog (9b), were synthesized. The diazen-1-ium-1,2-diolate compounds 12a-b released a low amount of NO upon incubation with phosphate buffer (PBS) at pH 7.4 (6.1-8.2% range). In comparison, the percentage NO released was significantly higher (76-77% of the theoretical maximal release of two molecules of NO/molecule of the parent hybrid ester prodrug) when the diazen-1-ium-1,2-diolate ester prodrugs 12a-b were incubated in the presence of rat serum. These incubation studies suggest that both NO and the anti-inflammatory 5-(4-hydroxymethylphenyl)-1-(4-aminosulfonylphenyl)-3-trifluoromethyl-1H-pyrazole (10a), and its methanesulfonyl analog (10b), would be released from the parent NONO-coxib 12a or 12b upon in vivo cleavage by non-specific serum esterases. The hydroxymethyl compounds 10a-b were weak inhibitors of the cyclooxygenase-1 (COX-1) and COX-2 isozymes (IC(50)=3.7-10.5 microM range). However, the hydroxymethyl compounds 10a-b and the parent NONO-coxibs 12a-b exhibited good AI activities (ED(50)=76.7-111.6 micromol/kg po range) that were greater than that exhibited by the reference drugs aspirin (ED(50)=710 micromol/kg po) and ibuprofen (ED(50)=327 micromol/kg po), but less than that of celecoxib (ED(50)=30.9mumol/kg po). These studies indicate hybrid ester AI/NO-donor prodrugs (NONO-coxibs) constitutes a plausible drug design concept targeted toward the development of selective COX-2 inhibitory AI drugs that are devoid of adverse cardiovascular effects.     

Synthesis of new chemical entities from paracetamol and NSAIDs with improved pharmacodynamic profile

It was envisaged to combine high antipyretic activity of paracetamol into commonly used NSAIDs. To achieve this goal new chemical entities were synthesized by chemically combining paracetamol and NSAIDs, and biologically evaluated for their antipyretic, analgesic, anti-inflammatory and ulcerogenic potential. The acid chloride of parent NSAIDs was reacted with excess of p-aminophenol to yield the desired p-amidophenol derivatives (1B–7B). Acetate derivatives (1C–7C) of these phenols (1B–7B) were also prepared by their treatment with acetic anhydride, in order to see the impact of blocking the free phenolic group on the biological activity of the derivatives. All the synthesized p-amidophenol derivatives showed improved antipyretic activity than paracetamol with retention of anti-inflammatory activity of their parent NSAIDs. These compounds elicited no ulcerogenicity unlike their parent drugs.     

Topical anti-inflammatory activity of Bauhinia tarapotensis leaves.

The topical anti-inflammatory properties of Bauhinia tarapotensis Benth. (Leguminosae) leaves have been studied by the inhibition of the croton oil-induced ear edema in mice. A bioassay-guided fractionation showed an interesting anti-inflammatory activity of the chloroform extract, that justifies the activity of the whole herbal drug. The main anti-inflammatory principles of B. tarapotensis leaves are triterpenic acids of ursane and oleanane series. The antiphlogistic activity of mixtures constituted of two ursane and oleanane isomers with different hydroxylation pattern, in the ratio 2:1, is comparable to that of indomethacin (ID50 ranging from 95 to 147 microg/cm2 and 93 microg/cm2, respectively).     

Synthesis and biological evaluation of new 3-substituted indole derivatives as potential anti-inflammatory and analgesic agents

Treatment of 3-cyanoacetyl indole 1 with the diazonium salts of 3-phenyl-5-aminopyrazole and 2-aminobenzimidazole afforded the corresponding hydrazones 4 and 5. 3-Cyanoacetyl indole reacted with phenylisothiocyanate to give the corresponding thioacetanilide derivative 7. Treatment of 7 with hydrazonoyl chlorides afforded the corresponding 1,3,4-thiadiazole derivatives 8a-f and 9. Also, the thioacetanilide reacted with alpha-haloketones to afford thiophene derivatives 10a,b (tenidap analogues), or thiazolidin-4-one derivative 11. The newly synthesized compounds were found to possess potential anti-inflammatory and analgesic activities.     

Synthesis of novel of 2, 5-disubstituted 1, 3, 4- oxadiazole derivatives and their in vitro anti-inflammatory,anti-oxidant evaluation,and molecular docking study

A series of novel 2, 5-disubstituted 1, 3, 4-Oxadiazole derivatives as a potential anti-inflammatory, and anti-oxidant agent were synthesized via cyclisation. Hydrazide molecule treated with substituted acids in the presence of phosphorus oxychloride (POCl₃) as an efficient reagent as well as solvent by conventional method with shorter reaction time and excellent yield. The newly synthesized 1, 3, 4- oxadiazole derivatives exhibited excellent to good anti-inflammatory and anti-oxidant activities compaired to the standard drugs. Molecular docking study on the crucial anti-inflammatory target–cyclooxygenase-2 (COX-2) revealed the ability of the scaffold to correctly recognize the active site and achieve significant bonded and non-bonded interactions with key residues therein. This study could identify potential compounds which can be pertinent starting points for structure-based drug design to obtain newer anti-inflammatory agents.     

Design,synthesis and biological evaluation of vortioxetine derivatives as new COX-1/2 inhibitors in human monocytes

In order to identify a suitable alternative to non-steroidal anti-inflammatory drugs (NSAIDs) we aimed to develop derivatives of vortioxetine, a multimodal anti-depressive drug that has been shownpreviously to be endowed withanti-inflammatory activity in human monocytes/macrophages. Vortioxetine (1) was synthesized in good yield and different alkyl and aryl derivatives were prepared based on their structural diversity and easy availability. The compounds were tested on human monocytes isolated from healthy donors for theireffect on superoxide anion production and cytokine gene expression, and for COX-1/2 gene expression and activity modulation. Moreover, a docking study was performed to predict the interactions between the synthesized compounds and COX-1 and COX-2. Correlating experimental biological data to the molecular modelling studies, it emerged that among the novel compounds, 6 was endowed of antioxidant and anti-COX-1 activity, vortioxetine and 3 were good antioxidants and mild anti-COX-1/2 inhibitors, while 7 was a good anti-COX-1/2 inhibitor and 11 was more specific versus COX-2.